Cisco 1721 nvram error?

Sounds like the memory chip has slipped out of the seat slightly, else it went bad.

Isnt the chip builtin the mainboard?

There is a mini flash card that holds the IOS and config
http://www.cisco.com/en/US/products/hw/routers/ps221/products_installation_guide_chapter09186a00800c623b.html
I'm pretty sure this is where the boot image (config) is stored, but so is the IOS. Is the router booting into the full IOS, or the mini IOS?
What message do you get from "show flash:"  or "dir flash:"

What do you get if you do a "show file systems"? Is the nvram: file system mounted read-write (rw)? Can you paste the output here?
Cheers

This is the output:

Router#show file systems
File Systems:

     Size(b)     Free(b)      Type  Flags  Prefixes
           -           -    opaque     rw   archive:
           -           -    opaque     rw   system:
           -           -     nvram     rw   nvram:
           -           -    opaque     rw   null:
           -           -   network     rw   tftp:
           -           -   network     rw   snmp:
           -           -    opaque     ro   xmodem:
           -           -    opaque     ro   ymodem:
*   33292284     7270732     flash     rw   flash:
           -           -    opaque     wo   syslog:
           -           -   network     rw   rcp:
           -           -   network     rw   ftp:
           -           -   network     rw   http:
           -           -   network     rw   scp:
           -           -   network     rw   https:
           -           -    opaque     ro   cns:

Hmmm, this says you have no nvram. Can you also post the output from the following commands? "show version", "show running-config" (with the passwords removed). If the nvram is broken, we can resolve it by getting the configuration from a tftp server when it boots :-)

Router#show version
Cisco IOS Software, C1700 Software (C1700-ADVSECURITYK9-M), Version 12.4(3), RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2005 by Cisco Systems, Inc.
Compiled Fri 22-Jul-05 12:04 by hqluong

ROM: System Bootstrap, Version 12.2(7r)XM2, RELEASE SOFTWARE (fc1)

Router uptime is 2 weeks, 4 days, 8 hours, 16 minutes
System returned to ROM by power-on
System image file is "flash:c1700-advsecurityk9-mz.124-3.bin"


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States and local country laws governing import, export, transfer and
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third-party authority to import, export, distribute or use encryption.
Importers, exporters, distributors and users are responsible for
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agree to comply with applicable laws and regulations. If you are unable
to comply with U.S. and local laws, return this product immediately.

A summary of U.S. laws governing Cisco cryptographic products may be found at:
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If you require further assistance please contact us by sending email to
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Cisco 1721 (MPC860P) processor (revision 0x400) with 60957K/4579K bytes of memory.
Processor board ID FOC08530P3A (4222153392), with hardware revision 0000
MPC860P processor: part number 5, mask 2
1 Ethernet interface
1 FastEthernet interface
32K bytes of NVRAM.
32768K bytes of processor board System flash (Read/Write)

Configuration register is 0x2102

--------
I cannot post an entire running config here, because there is too many sensitive informations in it, even if with omitted password. Is there a specific line/s you want?

Can you post result of
Router#dir flash:
or  show flash:

Router#dir flash:
Directory of flash:/

    1  -rw-    13359840  Dec 13 2005 21:03:13 +00:00  c1700-advsecurityk9-mz.124-3.bin
    9  -rw-      304549  Jan 06 2006 17:05:06 +00:00  crashinfo_20060106-170506
   10  -rw-        1038  Apr 29 2006 09:41:43 +00:00  home.shtml
   11  -rw-        1830  Apr 29 2006 09:41:44 +00:00  sdmconfig-1721.cfg
   12  -rw-      102400  Apr 29 2006 09:41:45 +00:00  home.tar
   13  -rw-      242285  Apr 29 2006 09:41:48 +00:00  attack-drop.sdf
   14  -rw-     1052160  Apr 29 2006 09:42:07 +00:00  common.tar
   15  -rw-     4734464  Apr 29 2006 09:43:10 +00:00  sdm.tar

33292284 bytes total (7270732 bytes free)

Why is that?

When a router crashes unexpectedly sometimes it creates a complete memory dump and saves it as a crashinfo file. This file is just taking up space and not leaving you enough room to do what you need to.